TorqueList Original Technical Art
Pontiac 347 V8
V8 · N/A
Pontiac · Traditional Pontiac V8
The 1957 Pontiac V8 offered with four-barrel, Tri-Power and Rochester fuel injection.
347
Cubic inches
The 347 marked Pontiac's shift from simply offering a modern V8 to aggressively developing performance versions, including Tri-Power, fuel injection and NASCAR-oriented combinations.
Displacement
347 ci
Bore
3.9375"
Stroke
3.5625"
Years
1957
Key Takeaway
The 347 retained the 3.9375-inch bore and lengthened stroke to 3.5625 inches. Pontiac offered unusually ambitious induction choices for 1957, including Tri-Power and mechanical fuel injection, showing how quickly the new V8 family was being pushed toward performance.
The 347 retained the 3.9375-inch bore and lengthened stroke to 3.5625 inches. Pontiac offered unusually ambitious induction choices for 1957, including Tri-Power and mechanical fuel injection, showing how quickly the new V8 family was being pushed toward performance.
Variant-specific values are labeled. Engine families that span multiple years or RPOs can have different heads, cams, induction and rotating parts, so the exact code/year always takes priority.
Pontiac offered a 317-hp Tri-Power NASCAR-oriented 347 combination during the division's accelerating factory performance program.
The 347 foreshadowed the performance identity that would explode with the 389 and 421.
347 cu in / 5.7 L with 3.9375 x 3.5625-inch bore and stroke.
90-degree OHV V8 with cast-iron construction.
Available with two-barrel, four-barrel, Tri-Power, or Rochester mechanical fuel injection depending version.
Factory output ranged up to 317 hp.
History · context · related reading
The 347 was the point where Pontiac's new V8 stopped being just a modern engine and became a serious performance platform. Tri-Power and fuel injection appeared within only two years of the architecture's debut.
Documented motorsport results
1957
317-hp competition specificationDriver
Pontiac factory-supported racers
Car / engine
1957 Pontiac with 347 Tri-Power
The 347 was offered in a special high-output Tri-Power specification as Pontiac pushed deeper into stock-car competition.
TorqueList Garage Reference Series
The same Engine Library data now powers a more detailed mobile-friendly catalog with technical specs, variants, engineering notes, history and related stories.